The industrial preparation of Ethanol from Ethene.

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Transcript of The industrial preparation of Ethanol from Ethene.

Direct Hydration of Ethene Industrial Production of Ethanol from Ethene Or Also Known As... A Presentation by Jamie Tolan & Farhad Jokhi Ethene... Properties: Appearance: Colourless GasMelting Point: -169.2°CBoiling Point: −103.7 °CStandard State: Gas Uses: Major industrial reactions of ethene in order of scale:1) polymerization,2) oxidation,3) halogenation,4) alkylation,5) hydration. Ethene can be hydrated to give ethanol, but this method is rarely used industrially. In the United States and Europe, approximately 90% of etene is used to produce three chemical compounds: ethene oxide, ethene dichloride, and a variety of polyethenes. Ethanol Properties: Appearance: Colourless LiquidMelting Point: −114 °CBoiling Point: 78 °CStandard State: Liquid No longer a double bond between the Carbon atoms Hydroxyl group has replaced the Hydrogen Ethene Ethanol Uses: Ethanols primary use is as a motor fuel and as a motor fuel additive. Another major use of Ethanol is in the production of acloholic beverages. The Mechanism For Hydration of Ethene General Formula (Note)- Blue Arrows Indicate the Movement of Electrons Step 1 This molecule is called the carbocation intermediate due to the positive charge on the carbon atom The conditions for this reaction are 300°C and 60-70 atmospheres, in the presence of steam. Step 2 Here we see the carbocation intermediate from the previous stage. Step 3 Finally, one of the hydrogens on the oxygen is removed by reaction with the dihydrogenphosphate ion, H2PO4-, formed in the first step. Our product is formed The catalyst is regenrated The carbocation reacts with one of the lone pairs on a water molecule Economic Advantages Disadvantages Environmental Advantages Disadvantages The End

Thank you for watching... Ethanol Although the initial yield is only 5 %, if unreacted steam and ethene are constantly recycled then the yield rises to 95% overall. The remaining 5% is due to side reactions which produce methanol and polyehtene. High temperatures and pressures expend lot of energy which means it costs a large amount of money to produce ethanol on an industrial scale. Most of the products are not wasted and are not toxic or harmful to the environment. High temperatures and pressures require a large amount of energy when manufacturing ethanol, which means using large amounts of fossil fuels